Abstract
The aim of this study was to analyze distribution and development of stress-stress state in structured rock specimens subject to uniaxial and biaxial loading to failure using digital speckle correlation method. Within the experimental analysis of wave processes in the block-hierarchy structure of geomedia (uniaxial and biaxial compression and shearing of prismatic geomaterial specimens), the authors revealed the fact of initiation of low-frequency micro-deformation processes under slow (quasi-static) disturbances. The estimation of the deformation-wave behavior of geomaterials as the “summed” contributions made by elements of the scanned surfaces with different-oriented (in-phase and anti-phase) oscillations has been performed using the energy approach that is based on the scanning function R, analogous to the “center of mass” in the classical mechanics.
Highlights
Dynamic advance of the theory of pendulum-type waves in stressed geomedia with block-hierarchical structure [1]-[3] has initiated a new research trend concerned with focal areas/sources of disastrous events
Within the limits of the experimental study of wave processes in the geomedia with structural hierarchy of blocks, the earlier found phenomenon of low-frequency microdeformation generated by slow force has been confirmed
The energy approach to evaluation of deformation-wave processes is based on the scanning function R that is the equivalent of the notion of the “center of mass” in the classical mechanics, and describes the way of determining the reduced center of seismic energy release for a set period of time within the limits of a given volume of rock mass
Summary
Dynamic advance of the theory of pendulum-type waves in stressed geomedia with block-hierarchical structure [1]-[3] has initiated a new research trend concerned with focal areas/sources of disastrous events (earthquakes, rock bursts etc.). Based on the analysis of the behavior of the functions ε х , ε у , ε ху , Rx (t ) , Ry (t ) and Rxy (t ) , the following pre-failure features are definable in the specimens: 1) the components of same deformation (the microstrains ε у , ε ху ) in areas 1 and 2 differ significantly; 2) the amplitude of oscillation of the microdeformation components in the area of failure significantly exceeds their oscillation amplitude in the undisturbed area, which implies the higher deformation velocity and the change of the strain state type (it is observed for the microstrains ε у , ε ху ); 3) the scanning functions have oscillatory character, which gives evidence оf inhomogeneity of the inner strain state of geomaterial. A cleavage crack has stepped surface and forms angles of 20 40 ̊ with the direction of the axial force, i.е. it creates combination of microcracks in the directions of ε у and ε ху
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
